FIELD OF THE INVENTION
The invention belongs to the automotive arts. Specifically, the invention relates to a control unit for a motor vehicle. The control unit comprises a base plate formed with press-fit openings in an outer area; a conductor-track carrier mounted on the base plate and formed with conductor tracks that are routed to the press-fit openings and that each have electric contacting tabs formed in the area of the press-fit openings. An electronic circuit is electrically connected to the conductor-track carrier, and a housing cover is coupled in an oil-tight manner to the base plate. A plastic supporting body is coupled to the base plate in a bearing area and at least one electric conductor is encapsulated within the supporting body. A contact pin that is electrically connected to the conductor emerges from the supporting body in the bearing area projects into a press-fit opening in the base plate and there establishes an electrical connection with a contacting tab of the conductor-track carrier. The invention further pertains to a method of producing a control unit of that kind.
The integration of engine and gearbox control units into the motor-vehicle subassembly that is to be controlled by the control unit (i.e., the engine or gearbox) is already known in the art. Integrated control units of the kind must be sealed off from oil, remain functional over a wide temperature range (about -40.degree. C. to 140.degree. C.) and be highly resistant to vibration (up to about 40 g). Furthermore, the units must meet particularly high reliability requirements since removing the units from the engine or the gearbox and refitting them, as required for repair, is very costly.
A control unit as generally described above is disclosed in the commonly assigned German patent application 197 12 842.4 (published after the priority date of this application). The earlier disclosure has a housing of simple construction which can be produced economically. The control unit is supported by a supporting body in which the housing cover is integrally formed. The electrical conductors in the supporting body are connected electrically to the electronic circuit in the control-unit housing by means of conductor pins, which are provided in a bearing area of the housing cover, project into insulating bushes of the base plate and there in each case establish an electrical connection with a conductor-track tab of the conductor-track carrier. The tab is pulled into the insulating bush.
That control unit essentially meets the above-mentioned requirements with regard to oil-tightness, ability to function over a wide temperature range, and vibration resistance.